Anti-Congress, like one Republican force from the right (6)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

Reversal of ( … from the right , in an across clue) [ DIG(to like/to be into something, an activity like a sport, say) + I(Roman numeral for “one”) + R(abbrev. for “Republican”) + F(symbol for “force” in physics).