Washington (CNN) - Senior Obama campaign official Steve Hildebrand is eyeing a Democratic primary challenge to South Dakota Rep. Stephanie Herseth Sandlin, a decision he said hinges largely on whether she votes against health care reform later this week.
Hildebrand, deputy national campaign manager for Obama's presidential campaign, told CNN in an exclusive interview that he has been frustrated with Herseth Sandlin's voting record for some time, especially her decision to oppose the House health care reform bill in November. The House is expected to vote again on the issue later this week and a Herseth Sandlin spokesperson has said she plans to vote no again.
"I want to see how she votes on health care," Hildebrand said. "If the vote is very, very close and we lose it or come close to losing it, I will take a serious look at challenging her."
"She is on the wrong side of history," he added.
A Herseth Sandlin spokesman declined to comment on the potential primary challenge.
Hildebrand said he has not spoken to the White House about a potential run, nor has he reached out to Sen. Tim Johnson, D-South Dakota, or former Senate Majority Leader Tom Daschle, D-South Dakota. Hildebrand, a close political advisor to Johnson and Daschle, said if he decides to run he will have a "conversation with them."
"But I would not expect them to go against an incumbent within their party," he said.
On Monday, Hildebrand sent an e-mail to South Dakota Democrats urging them to pressure Herseth Sandlin to support Obama's health care reform efforts. He accused the Democratic congresswoman of "siding" with the GOP and "the big insurance companies" on the debate over health care reform.
"The bill may not pass the House without Stephanie's support," Hildebrand said in the email. "What a tragedy if we came this far in our fight to get health insurance reform, only to see the bill die because a few of our own Democrats stood in the way. We need Stephanie's vote. It's critical."
He made no mention of a possible challenge to Herseth Sandlin in the note.
Hildebrand is the highest profile Democrat to openly talk about challenging a specific member of his own party over the health care issue, although the idea is picking up traction in some corners of the party.
Prominent Democratic strategist Donna Brazile wrote on her Twitter feed Monday that "If a handful of Democrats decide to defeat this bill, they deserve to get a primary challenge to defend the status quo & insurance industry."
And MoveOn.org sent an email to its members on the same day asking them to "pledge to support progressive primary challengers to House Democrats who side with Republicans."
Hildebrand said that if he decides to run, he will only accept contributions from South Dakotans and will cap the amount at $100. Widely credited with devising Obama's primary political strategy - including the Iowa caucus win - Hildebrand said he thinks he "could run a very credible race for about $150,000 to 200,000." Herseth Sandlin has more than $362,000 in the bank, according to her latest fundraising report filed with the Federal Election Commission.
The South Dakota primary is June 8.
At one time, Hildebrand said he "advised" Herseth Sandlin "on an informal basis" and even donated $500 to her campaign. But when she came on out in favor of a constitutional amendment to ban gay marriage, Hildebrand asked for his money back. Hildebrand, who is gay, is the principal in Hildebrand Strategies, political consulting firm based in Sioux Falls, South Dakota.