When a third party Christian Conservative is considered in the race for the White House, the candidate captures one of four Republican votes and a small minority of the overall vote. That significantly decreases support for Republican Rudy Giuliani and increases Democratic front-runner Hillary Clinton’s lead to double digits, according to a FOX News poll released Wednesday.

In a head-to-head contest, Clinton has a 4 percentage point edge over Giuliani -- 47 percent to 43 percent. Clinton has maintained a slim advantage over Giuliani for the last few months.

In a hypothetical three-way race, an unnamed Christian Conservative third party candidate receives the support of 14 percent of voters, and Clinton tops Giuliani by 10 points (44 percent to 34 percent).

Click here to view full results of the poll. (pdf)

Of recent third party candidates, Ross Perot received the highest percentage of the vote by garnering 19 percent in the 1992 presidential election.

Giuliani’s support among Republicans drops from 79 percent in the two-way race to 60 percent when the third party Christian Conservative is included.

By a 56 percent to 35 percent margin, self-identified Born Again Christians back Giuliani over Clinton. When given the option, about a quarter of this group says they would vote for a Christian Conservative candidate -- reducing Giuliani’s support by 20 points: Giuliani 36 percent, Clinton 30 percent and the Christian Conservative 26 percent.

Among conservatives, Giuliani’s support falls from 57 percent in the head-to-head race against Clinton to 42 percent when a third-party conservative is included.

"While some of the conservative Christian leaders are sounding more positive about Mitt Romney despite his Mormonism, by and large they are still very negative about Giuliani," said John Gorman, chairman of Opinion Dynamics. "A significant fraction of voters who might otherwise support the Republican are also clearly not fans of the former mayor. If given a chance, they say they’ll vote for someone else. This might diminish somewhat if the election of Clinton becomes more threatening to them, but given the narrowness of recent elections, even a few points could be decisive."

The results are essentially the same whether the three-way match up includes an unnamed third party Christian Conservative candidate or asks about "Conservative third party candidate Mike Huckabee."

In other two-way matchups, the poll finds that Clinton tops McCain by 3 points, and bests both Fred Thompson and Mitt Romney by 12 points.

The national telephone poll was conducted for FOX News by Opinion Dynamics Corp. among 900 registered voters from Oct. 9-10. The poll has a 3-point error margin.