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Presumptive GOP nominee Mitt Romney today announced that Rep. Cathy McMorris Rodgers, the highest-ranked Republican woman in Congress, will serve as the campaign's point person in the House of Representatives.

Romney and McMorris Rogers are set to appear at the fundraiser in the Seattle area tonight, where Romney is expected to personally announce the appointment of the Washington state Republican to her new role with the campaign. A GOP source expects that the fundraiser will collect up to $4 million for the Romney campaign.

In her new capacity, McMorris Rodgers will serve as liaison between the campaign and Republicans in the House, where she is the fifth-ranked GOP leader as vice chair of the House Republican Conference.  She'll essentially quarterback the relationship with the Romney campaign and the Republican majority in the House of Representatives, helping coordinate and align the GOP's message on both fronts.

"I am honored that Congresswoman McMorris Rodgers has agreed to take a leadership role on behalf of the campaign," Romney wrote in a statement announcing the decision. "She understands the impact of the economic challenges Americans face and the need to put our country on a better track. As a member of the leadership team in the House, she will be a helpful partner in our efforts to ensure our focus remains on the critical issue of economic security for all Americans."

McMorris Rodgers, a four-term lawmaker in the House, has been considered by some congressional insiders as a long-shot wildcard as Romney's running mate. The two last campaigned together in March ahead of the Washington caucuses, which Romney won by 13 points.

"I am truly honored to serve as the leader of Mitt Romney's House team," McMorris Rodgers said. "Governor Romney has demonstrated the leadership and vision that we have been fighting for in Congress to stop runaway government spending and create an environment for job creation."

Across the Capitol, Sen. Roy Blunt, R-Mo., has led the Romney campaign's congressional outreach efforts since last fall. Blunt, who is vice chair of the GOP conference in the upper chamber, will continue to serve as the campaign's liaison to the Senate.

Blunt praised McMorris Rodgers as a "tireless public servant who will serve as a valuable leader" for Romney's campaign.

"President Obama's policies have failed to put people back to work and get our economy back on track, which is why I look forward to working with Congresswoman McMorris Rodgers and other leaders to help elect Governor Romney this November," he stated.

McMorris Rodgers said she is looking forward to the assignment and teaming with Blunt "in our effort to get our country back on the right track."

A GOP aide says McMorris Rodgers and Blunt will personally meet with campaign officials from Team Romney later this week to work out the details of the assignment.

ABC News' Emily Friedman contributed to this report