DENVER – Looking to shore up support in a battleground state he easily carried four years ago, President Barack Obama began a two-day swing through Colorado Wednesday with a speech to an audience of mostly women.

Following the model Sen. Michael Bennet used to eke out a narrow and unexpected victory here in 2010, Obama is focusing the attention of female voters, a key demographic in this critical state, on policy issues related to their own health.

“The choice we face this November could not be bigger,” Obama said. “This is a choice between two fundamentally different paths for our country. That’s true for everyone, but it’s especially true for women.”

Embracing the term “Obamacare”, Obama underlined the provisions in the Affordable Care Act that are helping women and seniors get more comprehensive and affordable healthcare; and he criticized Republican Mitt Romney for campaigning on a promise to repeal the law.

“When it comes to a woman’s right to make her own healthcare choices, they want to take us back to the policies of the 1950s,” Obama said. “The decisions that affect a woman’s health, they’re not up to politicians or insurance companies. They’re up to you. And you’ve got a president who will fight to keep it that way.”

Sandra Fluke, the Georgetown law student who Rush Limbuagh called a “slut” after she testified before Congress that free birth control is an essential component of women’s health care, introduced Obama to the crowd inside the Auraria Event Center.

“When I became attacked for speaking out before Congress, I realized more than ever than this is an election that will determine whether the rights women have fought for will be rolled back,” Fluke said.

“Thankfully, we have a president who will fight to defend those rights, especially the right to affordable healthcare. Our access to healthcare should never depend on what gender we are.”

Fluke noted that, after Limbaugh’s disparaging comment, she got a phone call from the president.

“And all Romney could say was, ‘those weren’t the words I’d choose’,” Fluke said Wednesday. “Well, Mr. Romney, this November you won’t be the candidate we will choose.”

In his remarks, Obama made it clear that healthcare reform mandates that most healthcare plans cover the cost of birth control while offering exceptions for religious organizations.

“You can protect a woman’s right to healthcare and freedom of religion,” Obama said.

Obama also ripped Romney for his promises to “kill Obamacare dead” and to get rid of Planned Parenthood, and for his support or Mississippi’s failed “Personhood Amendment”.

“We are not going, backwards, Denver,” Obama said. “We are moving forward.”

The Romney campaign Wednesday dispatched Ohio Sen. Rob Portman, likely among the final front-runners to be Romney’s running mate, on a bus tour up and down the Front Range, countering Obama’s message with their own.

After events in Loveland, Adams County and Lakewood Wednesday morning, Portman arrived for a rally outside Sports Authority Field at Mile High, where Obama accepted the Democratic presidential nomination four years ago.

“Those promises have not been met,” Portman told a crowd of about 50 people. “Our country is headed in the wrong direction. But, thankfully, Mitt Romney is a man who can turn it around.”

In Boston Wednesday, Romney’s campaign also rolled out a “Women for Mitt” coalition, headed up by the candidate’s wife, Ann Romney.

An email to reporters listed state chairs from 41 of 50 states, but Colorado was among the nine states without a top female surrogate listed.

From Denver, Obama flew to Grand Junction for another event there Wednesday afternoon and then on to Pueblo where he’ll spend the night ahead of Thursday events there and in Colorado Springs.

Those events will focus more on the President’s message that his policies will help the middle class and touch on Romney’s opposition to a wind energy Production Tax Credit that could cost Colorado a few thousand jobs, according to an Obama staffer.

The Romney campaign has its own counter-programming scheduled for Thursday as well.

Louisiana Gov. Bobby Jindal, also thought to be in the mix as a potential running mate, will be on the Romney bus Thursday along with Congressman Jason Chaffetz, R-Utah, trailing Obama with events in Pueblo, Fountain and Colorado Springs.

Setting the mood for the President’s longest campaign swing through the state to date, a flurry of new polls paint a confusing picture of the race in Colorado.

A survey from CBS News and Quinnipiac University released Wednesday shows Romney leading Obama in Colorado by a 50-45 percent margin.

Portman, not surprisingly, mentioned it in his remarks.

“”Folks that’s the trend you see in Colorado, something’s happening here on the ground,” Portman said.

The Quinnipiac poll stands in stark contrast to two other polls released Tuesday, one of which, a survey by Public Policy Polling, showed Obama with a 49-43 percent lead; and another, conducted by Rasmussen Reports, that showed the race in Colorado deadlocked at 47 percent apiece.