Even as the White House increasingly dispatches its most respected surrogates to Capitol Hill to try to sell its priorities, Senators in both parties say the Bush administration continues to lack the political clout it needs to either cement GOP unity or negotiate in good faith with longtime rival Democrats.

The situation has put the White House at a political crossroads, as it tries to outmaneuver the Democratic majority on Iraq while also brokering deals with the opposing party on domestic items such as comprehensive immigration reform. Many Senators say they are getting mixed signals from an administration that is lining up an impressive series of meetings with its more popular Cabinet secretaries and appointees, even as it threatens vetoes at nearly every turn.

“We’re always willing to talk and there’s a lot more discussions going on, but in the end there has to be a give and take,” said Sen. Debbie Stabenow (D-Mich.). “And so … it’s different in that we’re having more discussions, but if we don’t see a willingness to really work together and compromise and come to some common ground, that will tell us what’s really going on.”

“They are certainly trying much harder to engage people, and they are doing it with people who are good at it,” noted Sen. Judd Gregg (R-N.H.), the ranking member on the Budget Committee. “You’ve got to respect that. But the fact of the matter is their political capital is so low with the Iraq situation, they just don’t have the cards to play.”

Not oblivious to public opinion or the Congressional margins, White House officials acknowledge they are looking to their strongest weapons — surrogates and the veto pen — to try to shepherd through an agenda against a new Democratic majority.

“Any president’s political capital can increase or diminish based on how effectively he uses his assets,” said one White House official, speaking on the condition of anonymity. “Cabinet secretaries are assets and the veto pen is an asset.”

President Bush certainly is making use of both, having vowed to veto scores of bills after six years of using the blocking mechanism just once, when he nixed a bill last year to provide federal funding for embryonic stem-cell research. The president issued his first veto against the Democratic Congressional majority last month when he rejected the Democratic version of the emergency war spending bill that contained a timeline for withdrawing troops from Iraq.

On the outreach front, Bush ostensibly has altered his Congressional approach as well. Since the beginning of the year, the president’s Cabinet has spent countless hours on the Hill trying to craft legislative agreements on domestic priorities from taxes and trade to energy and health care.

The most notable example of engagement so far has come on immigration reform, where Homeland Security Secretary Michael Chertoff and Commerce Secretary Carlos Gutierrez spent the past three months meeting privately with Senate Republicans and later Democrats to hatch a compromise proposal.

But Chertoff and Gutierrez aren’t the only representatives of a heightened Hill presence by Bush’s senior team. Office of Management and Budget Director Rob Portman, Treasury Secretary Henry Paulson, U.S. Trade Representative Susan Schwab and White House Chief of Staff Josh Bolten are among those prominent advisers circling lawmakers these days trying to unify Republican Senators while seeking compromise with the Democrats on key policy priorities.

Even Bush himself has upped his direct face time with lawmakers as he holds regular bipartisan sessions with Congressional leaders as well as with his own party. Bush met Tuesday morning with House and Senate Republican leaders and later was set to sit down with a group of rank-and-file GOP Members on immigration reform.

“You’ve got to deploy your assets,” the White House aide said. “The Cabinet is full of Senate-confirmed people, all of whom have independent relationships with Senators and Members of Congress.”

But Bush’s task is complicated by the fact that many conservatives are wary of his immigration stance, while GOP moderates have grown increasingly nervous about Iraq.

“The veto pen is the best thing the president has in his arsenal and it gives him the most clout,” noted a senior Senate GOP aide. “But his standing with Congressional Republicans is probably at an all-time low because the major issues he wants us to tackle are extremely unpopular with the war in Iraq and immigration. The best thing he can do is just stop bad policy.”

Senate Minority Whip Trent Lott (R-Miss.) said Bush’s current political standing aside, the White House is doing what it must in a new environment that has left Republicans without control of the Congressional agenda. Lott said the administration seems to be “getting its sea legs” and is flexing its muscle as it probably should have done during the previous six years when the GOP was in charge of Congress.

“They are coming to terms and dealing with Republicans in the minority,” Lott said. “They have to get more engaged and they are getting involved more. But they still have the ultimate weapon, which is the veto”

That looming veto has made Senate Democrats wary of Bush’s sincerity when deal-making, perhaps even more so than did his six years of virtual neglect of them as the minority party. As one senior Democratic Senate aide put it: “They haven’t really shown a propensity to negotiate on anything, ever. It hasn’t been their default position.”

At the same time, however, Senate Democrats understand that regardless of whether they trust Bush, they can not legislate in a vacuum.

“The president always has clout by the virtue of the office and regardless of whether an individual is high or low in the polls, the president as the officeholder has clout,” said moderate Sen. Mark Pryor (D-Ark.). “He does have clout, but what I think a lot of people in the Congress would like to see is the president actually get his hands dirty in legislation. … I think most Republicans and Democrats welcome him to the legislative arena.”

“Engagement is a way to regain it or enhance” Bush’s influence, added Sen. Mel Martinez (R-Fla.). “It can’t do anything but help. It’s about getting things done. At the end of the day this is an opportunity to get the more difficult things done. Immigration will be the test.”

Senators are waiting to see how the White House’s role in the immigration debate plays out, privately insisting that Bush will have to do some heavy lifting in his own party if there’s a chance for a bipartisan package this year. Democratic House leaders have suggested Bush needs to corral 60 to 70 Republican Members to even bring the delicate Senate package to the House floor this year.

Senators in both parties say that unlike the previous Congress, when the White House largely sat on the sidelines, Bush does seem to recognize the new dynamics — not only by enlisting Chertoff and Gutierrez months ago to help put together a Senate compromise but also by already hosting some meetings with GOP lawmakers to try to build support Congress-wide.

“These are tough times and this president is trying to achieve as much as he can,” said Sen. John Cornyn (Texas), the vice chairman of the Republican Conference. “Just because times are tough, doesn’t excuse you from trying to get things done.”

Even so, Sen. Ben Nelson (Neb.), another moderate Democrat who sometimes sides with the GOP on controversial legislation, said the current partisan political climate makes compromising across the aisle increasingly problematic.

“I think it’s very difficult to negotiate in this environment,” Nelson said. “I negotiate with the people in the White House that I know I can take at their word. … I deal with my colleagues here, same thing. I want to be sure that I deal with people I know I can trust on both sides of the aisle, and that’s the way I do it.”