President Obama already supported marriage equality during the 2008 presidential campaign, according to a one of his closest advisors. In his new memoir, Believer: My Forty Years in Politics, chief political strategist David Axelrod says his former boss misled Americans about his position for political reasons.

“I’m just not very good at bullshitting,” the future president reportedly told him at the time.

Axelrod says he knew Obama supported same-sex marriage, but he counseled him to publicly support civil unions instead, as most of the country had not come around. At that time, only 40% of Americans favored marriage equality.

“Opposition to gay marriage was particularly strong in the black church, and as he ran for higher office, he grudgingly accepted the counsel of more pragmatic folks like me," writes the former advisor. "[He] modified his position to support civil unions rather than marriage, which he would term a ‘sacred union.’”

When President Obama did come out in support of full marriage equality, in an ABC News interview in May 2012, he claimed his view on the subject had "evolved," a tactic employed by other politicians who similarly changed their position.

In a 2014 interview with The New Yorker, Obama said "ultimately, I think the Equal Protection Clause [of the Constitution] does guarantee same-sex marriage in all 50 states."

“Having prided himself on forthrightness, though, Obama never felt comfortable with his compromise and, no doubt, compromised position,” Axelrod writes. “He routinely stumbled over the question when it came up in debates or interviews.”

Back in 1996, when he was running for the Illinois state Senate, Obama answered a questionnaire stating “I favor legalizing same-sex marriages and would fight efforts to prohibit such marriages.” But when that survey came to light, White House communications director Dan Pfeiffer said it had been filled out by someone other than the future president. Twelve years later, on the campaign trail, he stated marriage “is the union between a man and a woman,” adding that "God’s in the mix.”

The President didn’t publicly announce his support for same-sex marriage until after Vice President Joe Biden did so on Meet the Press. But Axelrod claims, by that point, he'd been pressing advisors for months for a way to address the issue.

"If Obama’s views were 'evolving' publicly, they were fully evolved behind closed doors. The president was champing at the bit to announce his support for the right of gay and lesbian couples to wed."

Believer: My Forty Years in Politics goes on sale February 10.