The Republican National Committee's top fundraiser is stepping down this week as he prepares to join New Jersey Gov. Chris Christie's prospective presidential campaign.

Texas-based fundraiser Ray Washburne told The Associated Press on Monday, "I won't be the national finance chairman at the end of the week." He declined to comment further because Christie has yet to announce his 2016 intentions.

The move comes as White House prospects begin speeding up their 2016 timelines because of the aggressive steps taken by former Florida Gov. Jeb Bush, who has hosted private meetings with top political donors in recent weeks. Former Republican presidential nominee Mitt Romney told donors late last week that he, too, is thinking about running, adding his name to the list of as many as a dozen high-profile Republicans considering a campaign.

Christie may face more pressure than others to get in, because Bush and Romney are likely to attract some of the same establishment-minded donors. Washburne was a leading fundraiser for Bush's brother, former President George W. Bush. His move was first reported Monday by The New York Observer.

Christie's team is expected to start making moves to raise money for a prospective presidential campaign by the end of the month, according to a person who has been in touch with Christie's team, but who spoke on the condition of anonymity because the person was not authorized to discuss the plans publicly.

That could include the potential formation of a political action committee to begin raising cash that can be used to support a prospective campaign, the person said.

Christie's chief political adviser, Mike DuHaime, declined to comment.

Christie has been traveling across the country attending inauguration events for Republican governors he worked to help elect during his tenure as chair of the Republican Governors Association. The trips have given him the chance to travel to key early-voting and swing states, where he's been able to spend time with key officials and donors. He'll head to South Carolina and Iowa later this week.

While he's in South Carolina, Christie is scheduled to attend a meet-and-greet with elected officials and business leaders -- one of several events planned for the coming weeks.