1880 census Las Animas County Colorado pages 21 and 22:
Antonio Romero born about 1842 in New Mexico.
His wife Deluvina Gomez 32 born in New Mexico, daughters Basilia 8, Aurora 4, sons Apolonio 2, and Delecio 2 months. They lived next to Deluvina's parents, Francisco Gomez 53 and Soledad Sanchez 40, Victoria 12, Leandro 10.
In 1870 this Gomez family lived in Cucharas Huerfano County Colorado: Francisco Gomes 45, Soledad 40, Deluvina 22, Salome 15, Francisco 13 and Maria Victoria 3.
1870 census of Costilla Colorado page 8 & 9 I find a Antonio Romero 23 (1847) born in New Mexico. He lives with Miguel Espinosa and his wife Genoveva. I don't know if he is yours.
1860 census for Arroyo Seco Taos County New Mexico page 19 shows the Gomez family: Francisco Gomes 34, Maria Soledad Sanchez 40, Dilubina 8, Salome 5, Francisca 3. From here they left to Huerfano.
I look in the Walsenburg marriages and do not find a marriage for Antonio and Delubina. I also do not find one in Trinidad. Nor is there one listed in the Colorado marriages.
On the 1880 census it says their daughter Basilia was 8 (1872). I do not find her baptism in Trinidad. It is possible she was born in Huerfano County. If any one out there has the Walsenburg Baptisms maybe they could look for her.
If this is your Antonio Romero then your great grandfather had to have been in New Mexico in the 1840's.
I do not find a marriage for an Antonio Romero to a Antonia Rivera.
The state of Wyoming did not have a census until 1870. And there is no Antonio Romero there.