Marco Rubio spoke at CPAC. Paul Ryan did too. And so did Rick Perry, Ted Cruz and Sarah Palin. Even Donald Trump and Mitt Romney were on the program.

But not Chris Christie nor Bob McDonnell.

And that illustrates a big problem facing the Republicans.

If the GOP hopes to counter the belief it represents a narrow ideological fringe and revive its support among women, minorities and political moderates, it won't do so by showing a public face excluding those who don't always toe the party line.

To be sure, as American Conservative Union chairman Al Cardenas said, this week's CPAC - the Conservative Political Action Conference - was "a conservative conference, not a Republican party event."

But it's a major showcase for up-and-coming Republicans that has offered a window into the GOP ever since Ronald Reagan urged the party at its 1975 conference to reject President Gerald Ford's ideology of "pale pastels" for one of "bold colors," foreshadowing the conservative revolution that led to his 1980 presidential victory.

Christie, the New Jersey governor whose high job support and bipartisan backing has discouraged major Democratic opposition this year, was invited in 2012 "because he did a great job in N.J. facing up to the teacher unions, balancing the budget and cutting debt," Cardenas said in an email to Politico.

"This past year," he added, "he strongly advocated for the passage of a $60+ billion pork barrel bill, containing only $9 billion in disaster assistance, and he signed up with the federal government to expand Medicaid when his state can ill afford it, so he was not invited to speak."

Republicans have also been mad at Christie since he appeared with President Barack Obama to examine Hurricane Sandy's damage a week before the 2012 election.

McDonnell, another popular GOP state executive who like Christie is reportedly weighing a 2016 presidential bid, angered conservatives by agreeing with Virginia Democrats on a massive transportation funding measure that includes some tax increases to fix the state's roads. He also agreed to the Affordable Care Act's Medicaid expansion.

McDonnell will address a nearby Faith and Freedom Coalition prayer breakfast. But state Attorney General Ken Cuccinelli, an outspoken conservative who hopes to succeed McDonnell this year, was invited to speak at the main event.

The irony in excluding those two governors is that not only did they become GOP heroes when their 2009 victories revived party spirits after its 2008 loss, but they have shown that compromise can make a Republican governor popular in blue New Jersey and purple Virginia.

National Republicans - especially those in Congress - have yet to learn that lesson. By governing as centrists, the two have broadened their support outside the GOP base, an essential ingredient for successful Republican campaigns in swing states in 2016.

In fact, 2012 Republican nominee Mitt Romney would have fared better against Obama if he'd run as the moderately conservative governor he was in Massachusetts instead of moving to the right on issues like immigration and health care.

It's hard to believe Romney will revert to prior form when he addresses CPAC. Indeed, it's a bit of a mystery why he wanted to go, given that he's never seemed entirely comfortable with the party's right wing, even while adopting its positions.

In any case, it's a safe bet that the GOP presidential hopefuls addressing CPAC - Sens. Marco Rubio of Florida, Rand Paul of Kentucky and Cruz of Texas, Govs. Perry of Texas, Bobby Jindal of Louisiana and Sam Brownback of Kansas, and Ryan - will be competing with one another in touting their conservative credentials.

Meanwhile, the presence of Trump, the New York construction magnate and television star, threatens to give the entire meeting a far less serious tone than its promoters would like.

The exclusion of Republicans who dare to display even an iota of moderation from meetings like this only hardens the GOP's image as a rigidly ideological conservative party, thus reducing its chances of regaining national power.

Carl P. Leubsdorf writes for the Dallas Morning News. Email him at carl.p.leubsdorf@gmail.com.