After being outshone by Democrats in the first quarter of the 2010 cycle, Senate Republican candidates rebounded with a respectable showing in the second quarter — including a few bright stars who stood out above the rest.

With some reports still outstanding Wednesday evening, Florida Gov. Charlie Crist’s $4.3 million raised in just 50 days and Missouri Rep. Roy Blunt’s $1.4 million stood out as two of Republicans’ biggest bright spots in the quarterly fundraising war.

Crist’s haul in the open-seat race to replace retiring Sen. Mel Martinez (R) was a tour de force in a primary where he faces former state Speaker Marco Rubio (R). And while it’s too early to say if it’s a knock-out blow to Rubio, Crist’s money total was welcome news for the National Republican Senatorial Committee, which is backing Crist.

The NRSC also made a move during the second quarter to endorse Blunt in the open Missouri Senate race after he put up a mediocre first-quarter fundraising showing and seemed to be facing a competitive primary challenge.

But the second-quarter figures showed Blunt’s campaign is back on track with almost $1.8 million in cash on hand at the end of June and what appears to be a clear primary field. For now at least, Blunt can focus on the general election where Missouri Secretary of State Robin Carnahan (D) — who has raised over $1 million in each of the first two fundraising quarters — will be waiting.

Elsewhere, former Rep. Rob Portman (R-Ohio) was another bright spot for Senate Republicans. Portman ended June with $4.3 million in the bank — the most of any Republican not holding federal office — and raised $1.7 million in the past three months.

Ohio Lt. Gov. Lee Fisher, one of two viable Democrats running next year, announced he raised over $900,000 in the quarter and has almost $1.9 million in the bank. The other competitive Democrat in the race, Secretary of State Jennifer Brunner, will report raising $228,000 this quarter, according to the Dayton Daily News. Brunner’s poor showing, for the second quarter in a row, further solidifies her place as the underdog in the race.

Democrats weren’t without fundraising stars of their own this quarter.

Senate Majority Leader Harry Reid’s (Nev.) more than $3.2 million raised and $7.3 million in cash on hand are two major reasons that Republican dreams of knocking off the Senate’s top Democrat may be slipping away. Two other reasons are the fact that Republicans have yet to field a serious candidate in Nevada and the media circus that continues to follow Sen. John Ensign (R-Nev.).

Sen. Arlen Specter (D-Pa.) proved to be one of the top fundraisers among the candidates in his new party by bringing in $1.7 million in the quarter and ending June with $7.5 million in cash on hand.

But Specter will likely have to spend some of his burgeoning war chest on what is expected to be a bloody primary against Rep. Joe Sestak (D), who has all but announced he is in the race. Sestak announced he raised more than $1 million in the second quarter and he has more than $4.2 million in the bank.

Former Rep. Pat Toomey (R-Pa.) announced he raised $1.6 million — almost as much as Portman — for his Senate bid. Toomey, who was recently endorsed by the NRSC, had $1.1 million in the bank.

Republicans also continue to have a few trouble spots on the 2010 map, with Kentucky Sen. Jim Bunning at the top of the list.

Bunning, who is considered the most vulnerable Senator of the cycle in large part because of his poor fundraising, at press time had yet to release his second-quarter report.

Secretary of State Trey Grayson (R) raised more than $600,000 for his exploratory committee. Grayson said he would not run if Bunning stays in the race, but he has also made comments since then that seem to indicate he’s rethinking that pledge.

On the Democratic side, state Attorney General Jack Conway solidified his spot as the frontrunner in the race for his party’s nomination by bringing in more than $1 million more than his opponent, Lt. Gov. Daniel Mongiardo (D).

Conway raised $1.3 million to Mongiardo’s $303,000.

In Illinois, Rep. Mark Kirk (R), who is expected to announce his Senate candidacy on Monday, raised $590,000 in the quarter and had more than $1 million in cash on hand. Kirk is the chosen candidate of the party establishment, and now that he will have virtually all of the third quarter to fundraise as a Senate candidate, his October report is expected to reflect a much bigger number.

On the Democratic side in Illinois, state Treasurer Alexi Giannoulias had a respectable second fundraising quarter, bringing in $676,000 for a total of $1.8 million so far. Giannoulias reported $1.6 million in cash on hand. Giannoulias could face at least two other Democrats in next year’s primary.

Sen. Chris Dodd (Conn.), Democrats’ most vulnerable incumbent, raised a cool $1.2 million this quarter, bringing his cash-on-hand total to $1.8 million.

The frontrunner for the Republican nomination in Connecticut, former Rep. Rob Simmons, announced he raised $753,000 for his campaign and will report $558,000 in cash on hand.

In Louisiana, Sen. David Vitter (R) raised more than $1.2 million and showed $3.2 million in cash on hand at the end of the quarter. Vitter faces a competitive general election against Rep. Charlie Melancon (D-La.). Melancon, who has yet to officially declare for the race, raised $404,000 in the second quarter, which more than doubled his first-quarter haul. He had $1.2 million in cash on hand as of June 30.

Alexander Comisar and Jeremy B. White contributed to this report.