It has been two months since the Trump administration put the president's ban on people in the military into effect, and it has been two years since President Donald Trump first announced the ban in tweets that surprised even military leaders.

But Trump isn't convincing even his own supporters of the need for the ban.

A new poll from the Public Religion Research Institute shows that nearly two-thirds of Americans oppose the ban. And while there is, generally speaking, little change from when Trump first made the announcement in 2017, there is a notable shift among one group: Republicans.

While 37% of Republicans supported the idea of transgender personnel in the U.S. military two years ago, that number has increased to 47%.

The poll is the second this year to show that an increasing number of Republicans support allowing transgender troops. A Quinnipiac University poll conducted in 2017 showed 32%. By January of this year, that number rose to 40%.

Like the PRRI poll, Quinnipiac showed broad support for transgender troops among both Democrats and independents, meaning this is an issue on which Trump appears to be fighting an increasingly losing battle.

And it's a battle that is very much of Trump's own choosing. This wasn't even an issue that was on anyone's radar before the president tweeted out his decree in July 2017, declaring that the administration would "not accept or allow Transgender individuals to serve in any capacity in the U.S. Military."

The ban that has been put in place is slightly scaled back, although activists argue it amounts to what is effectively a ban on new transgender recruits.

The new poll is the second tidbit this week to push the ban into the news. Trump claimed in an interview in Britain last week that the military couldn't allow transgender troops because troops aren't allowed to take "any drugs." The Defense Department itself has contradicted him, saying troops are allowed to take all prescribed medications, including hormone treatments for gender dysphoria and other conditions having nothing to do with transgender troops' needs.

The PRRI poll measures Americans' acceptance of transgender people and rights in a number of different ways, including whether people support laws requiring people to use bathrooms corresponding to their birth gender; how comfortable people would be with transgender people in various aspects of their lives; and whether people believe there are more than two genders.

On most questions, Republicans were less accepting of the transgender community. But the poll suggests that even they are somewhat nuanced when it comes to their views.

For instance, PRRI asked respondents whether they believed there are only two genders. Among Republicans, 62% said they believed "strongly" that there were only two. Another 35% either believed that but not strongly (11%) or believed that there were a range of genders (24%).

And if the recent history of polling on LGBT rights has shown us anything, it's that public opinion on this is only likely to move in one direction — and that's away from where Trump is.