Supporters of Sen. Hillary Rodham Clinton’s (D-N.Y.) presidential bid sought to turn up the heat on Speaker Nancy Pelosi (D-Calif.) last week. But Democratic sources warn the result might be a chilly reception on Capitol Hill next fall.

In a private letter to Pelosi last week, nearly two dozen Clinton backers called on the Californian to curb her calls for superdelegates to align themselves with the Democratic candidate with the most pledged delegates. They included a less-than-subtle reminder about their status as major donors to the Democratic Congressional Campaign Committee, a fact probably already known by the veteran lawmaker.

While Democratic Members and Pelosi confidants agreed it is inconceivable the Speaker would turn a cold shoulder to a newly inaugurated Democratic president, many acknowledged privately that such heavy-handed tactics are also not likely to win an ally from a Speaker known for placing a high value on loyalty.

“It’s clear that the Clinton campaign doesn’t understand Nancy Pelosi. Threatening Nancy Pelosi is not effective,” said one Democratic aide, who asked not to be identified. “This is not a leader who responds well to threats. It was an ill-conceived tactic.”

Some Democratic leaders and senior Members contended that Pelosi won’t hold a grudge, asserting that she dismissed the letter out of hand.

“In the heat of these campaigns, people say things but … people get back together,” House Majority Whip James Clyburn (D-S.C.) said.

He said he spoke with Pelosi on Thursday, a day following the letter’s appearance in the media, but the Speaker did not raise the issue with him.

“I think if she had some concern about it, she would have said something to me about it,” Clyburn said, noting that he is close with BET founder Bob Johnson, who was among the nearly two-dozen Clinton backers signing the letter.

Readers of tea leaves attempted to interpret Pelosi’s comments on superdelegates. Some saw it as a nod to Sen. Barack Obama (D-Ill.), the leader of pledged delegates; others said it was a restatement of earlier pronouncements.

“The Speaker has exercised great discipline in being neutral,” said one senior House Democratic lawmaker who has endorsed Obama and spoke on the condition of anonymity. “I don’t think it will set up any difference. This is the season that we’re in.”

Democratic Congressional Campaign Committee Chairman Chris Van Hollen (Md.) criticized the donors’ letter, asserting a threat to reduce contributions for the House campaign committee undermines Democratic goals under the next president.

He observed that many of the superdelegates poised to play a pivotal role in the election are Democratic lawmakers who need the campaign committee’s support for re-election. “It would be counterproductive for donors to be undercutting efforts by House Democrats to expand our majority,” he said. “Whoever is president is going to want a strong working majority in the House of Representatives.”

Pelosi dismissed the letter in an interview with National Public Radio aired Tuesday: “[L]et me be as clear as I can be: That letter is unimportant.”

The Speaker appeared to briefly temper her rhetoric Tuesday. “Superdelegates [should be] voting their conscience but paying attention to the will of the people,” she said at a press conference, a step back from her conviction that superdelegates should adhere to the candidate leading the pledged delegate count. She later added that any outcome that appears to overturn the will of the voters could be “detrimental” to the Democratic Party.

Pelosi spokesman Nadeam Elshami dismissed the notion that campaign tactics would dampen the relationship between the Speaker and Clinton: “Speaker Pelosi has made it very clear we have two credible candidates … and she’s looking forward to working with the new Democratic president.”

Norm Ornstein, a Roll Call contributing writer and resident scholar at the American Enterprise Institute, said he believed the recent donor letter is “going to backfire very considerably” for the Clinton campaign, and could leave a lasting scar on her relationship with Pelosi, as well as with House Democrats.

Ornstein said he doesn’t believe Pelosi will make her personal feelings on the matter public, but “she will find, as she always does, ways to make not just Clinton, but the people who signed that letter, pretty unhappy.”

“It was a big misstep on Clinton’s part to threaten Pelosi publicly, which this was,” Ornstein said. “It was a big mistake on the part of the Clinton campaign and these donors to say that they will bring the entire House down with us if you don’t do what we want. Also, it indicates how some of these harsh feelings are going to remain for a long time.”

Erin P. Billings contributed to this report.