If enough of the business community speaks up in favor of a carbon fee, it will become the law of the land. That’s the number-one message we heard during two years of meetings with some 300 senators, House members, and congressional aides. Most of them were open to this solution to climate change, but they need to see evidence that business leaders “back home” are on the same page.

Can we mobilize those leaders? The latest encouraging sign came last week from Business Forward, a group of small business owners, executives, entrepreneurs, and investors from across the United States. This trade association held a series of briefings with CEOs and economists from across the ideological spectrum to examine specific tax proposals and their potential impact on business. The conclusion: Many business leaders agree that pricing carbon is a simple, fair, and market-based solution. It decreases the need for federal regulation and can reduce emissions more quickly and equitably.

The drive to enact a carbon royalty (or fee) received an important boost last week. South Carolina Senator Lindsey Graham became the first Republican in the Senate to publicly endorse a "price on carbon” to fight climate change.

"I'm a Republican. I believe that the greenhouse effect is real, that CO2 emissions generated by man is creating our greenhouse gas effect that traps heat, and the planet is warming," said Graham. "A price on carbon—that's the way to go in my view."

He said that he is working with Senator Sheldon Whitehouse (D, RI) on legislation. Whitehouse and Senator Brian Schatz (D-HI) introduced a carbon tax bill in July, appearing at the American Enterprise Institute (AEI) to announce it. Graham, who said he would take the idea to the White House for consideration, called for climate change legislation during the 2016 election but did not mention a price on carbon explicitly.

From our meetings with scores of senators and their aides over the past three years, we know that a number of them privately support this free-market idea or are at least open to it. We will try to persuade them to join Graham in speaking out publicly.

Harvey, congressional gridlock, the U.S. withdrawal from the Paris accord, climate change deniers in high places…. These are just some of the things that can discourage someone who believes we need to take action on climate change.

But there are also reasons to be upbeat:

• While Congress has a disproportionate number of members who are content to sit on their hands as the climate changes at an alarming pace, the House Climate Solutions Caucus has grown to include 52 members--half of them Republicans.

• After a bipartisan vote in July left climate language in the annual defense authorization bill, Climate Solutions Caucus Co-Chairman Carlos Curbelo voiced optimism that lawmakers may actually begin to engage earnestly on the subject. "We have a lot of Republicans, even from the deep South, who everyday come to me and say, 'Well, let's talk about this climate change thing and sea level rise,'" Curbelo told a Florida radio station. "There is growing interest, and my hope is that we can build that coalition, that bipartisan coalition, as quickly as possible just so that we can advance common-sense policy solutions."