Not so fast, Clinton supporters say

The drumbeat grows louder for Hillary Clinton to gracefully exit the stage and cede the spotlight to Barack Obama.

If he gets the expected win in today's primary in Oregon, Obama will declare loudly that he has the majority of all delegates to be chosen by voters in primaries and caucuses. He is 17 shy of that milestone on the path to the Democratic nomination.

UPDATE: Obama, previewing his speech tonight, said he planned to remind Americans of the "very unlikely journey" of his candidacy.

"The reason we've been successful is because the people in Iowa and all across the country have been willing to set aside their cynicism and doubt and vote their hopes," he said on MSNBC this afternoon. "Essentially it's a message thanking the American people for having the confidence that we can really change the country right now."

If he is the nominee, Obama said, he would offer a clear choice with John McCain, whom he said represents more of the same Bush policies at both home and abroad.

For his speech tonight in Iowa, he will have a new high-profile ally -- Iowa Democratic Party Chairman Scott Brennan will endorse Obama today, the Associated Press is reporting. And a growing number of leading Democrats say it's time to let Obama focus on Republican John McCain.

But Clinton and her loyalists are having none of that. She is expected to win in Kentucky, meaning she would have won four of the last six primaries.

A group of supporters, gathered as WomenCount PAC, placed a full-page ad in today's New York Times.

"Not so fast....Hillary's voice is OUR voice, and she's speaking for all of us," the headline says.

They say in the ad that they "stand united in our unwavering support for Hillary Clinton." "We know that when women vote, Democrats win. Now it is the responsibility of our party to hear our voices and count all of our votes. We want Hillary to stay in this race until every vote is cast, every vote is counted, and we know that our voices are heard."