Bush is Republic party member. see what he said

Former President George W. Bush congratulated President-elect Joe Biden in a phone call Sunday and said that, while President Donald Trump has the right to pursue legal challenges and recounts, the 2020 race was "fundamentally fair" and "its outcome is clear."

The gesture by Bush, the only living former Republican president, was a break from his party's outgoing president, Trump, who has so far refused to concede the race.
In the statement, Bush said he had called Biden and Vice President-elect Kamala Harris on Sunday.
"Though we have political differences, I know Joe Biden to be a good man, who has won his opportunity to lead and unify our country," Bush said. "The President-elect reiterated that while he ran as a Democrat, he will govern for all Americans. I offered him the same thing I offered Presidents Trump and Obama: my prayers for his success, and my pledge to help in any way I can."
Bush also offered congratulations in the statement to Trump "on a hard-fought campaign," nodding to his "extraordinary political achievement" of winning the votes of more than 70 million Americans, the second-most in history behind Biden. "They have spoken, and their voices will continue to be heard through elected Republicans at every level of government," Bush said.
Bush in 2000 was elected by a much smaller margin than Biden, with his race against Democratic then-Vice President Al Gore coming down to 537 votes in Florida and a Supreme Court decision in December. He said Trump "has the right to request recounts and pursue legal challenges," but said Biden's win was clear.